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--- DISTRIBUTIONAL REFERENCES Colorado River Drainage--General Colorado River Fishes Recovery Team. 1988. Bonytail chub (Gila elegans) revised recovery plan (draft). U.S. Fish & Wildlf. Serv., Denver. 41 p. Provides map and description of presumed former range of bonytail (major streams of entire Colorado River basin, including mainstem from mouth to above Grand Junction, Colorado, and into lower Gunnison, Gila River, lower Little Colorado, San Juan, and Green River system into Wyoming and lower Yampa area). Also provides map of possible present distribution based on records over past two decades (lower Colorado in lakes Havasu and Mohave, upper Colorado at Cataract Canyon and Black Rocks, Green River near Desolation Canyon and in lower Yampa). Gives a summary of literature records of G. elegans and discusses the precipitous decline of this species. Bonytails disappeared from the lower basin except for in the above-mentioned reservoirs by about 1960. They were numerous in the upper Green in the 1960's but essentially disappeared a few years after closure of Flaming Gorge Dam. Since that time, collections (all one or few specimens) have been extremely sporadic and scattered in upper basin localities noted above. Also notes that, because both G. elegans and G. robusta were referred to as bonytails for many years, some putative records of elegans may be based on the latter. Colorado River Fishes Recovery Team. 1988. Humpback chub (Gila cypha) recovery plan (draft). U.S. Fish & Wildlf. Serv, Denver. 37 p. Provides a general summary of historic and present known distribution of humpback chub. Historic range is uncertain but included at least the lower Colorado and Little Colorado rivers in the Grand Canyon area and, in the upper basin, the main Colorado, Green, White and Yampa rivers. It probably existed in canyons below Hoover Dam, Arizona, before that structure was completed in the 1930s. The Grand Canyon population is thought to have declined drastically following the completion of Glen Canyon Dam in the early 1960s with a substantial population remaining only in and near the lower Little Colorado River (lower 13 km). In the upper basin, populations occur in Cataract Canyon above Lake Powell, Utah, at Black Rocks and Westwater canyons on the Colorado on the Utah-Colorado border, in the Green River in Desolation and Gray canyons, and in the Green and Yampa rivers in Dinosaur National Monument. A few other records are from scattered canyon localities in the upper basin and 25